View Full Version : Servo repairs?

05-27-2020, 08:02 PM
Has anyone had experience repairing Trutrak servos?

Had a DSB-C roll servo go out. Completely stopped providing torque sufficient to move controls, not shear screw. Makes anemic stepping sound

Trutrak agreed sounded like servo, suggested sending to mid-continent for repair. Cost new is bout $800. I?ll call mid-continent, but if expensive and will take time to do, maybe worth buying new?

Salt Lake City (KBTF)

D Weisgerber
05-27-2020, 09:44 PM
One of the wires on the 9 pin connector controls the torque to the servo, if that wire is broken you will get the stepping sound but it won't move.

D Weisgerber
05-27-2020, 09:53 PM
I just looked at the wiring diagram, pin #16 on the 25 pin connector goes to pin #6 on the 9 pin connector on the roll servo. I would check the continuity between those pins before I had the servo rebuilt.

05-27-2020, 11:06 PM
Man, if that works, you're due about $800 of your favorite beverage, and maybe it teaches the Bendix techs a thing or two!

It totally acts like a torque issue, - loose wire would be a great explanation for the sudden onset.

Thanks - Update tomorrow!


05-31-2020, 09:33 PM
I have both a pitch and roll servo that I am removing from my -10 this week that I plan on selling if you need an alternative

05-31-2020, 10:47 PM
Thanks, Bill,

Might be in the market- continuity on torque wire is good, and 5 v when autopilot on. The control arm just freely pivots. Going to give mid-continent a ring. Trutrak used to refurbish for less than half the new price, but have no idea what to expect now that they outsource.... let me know when you decide to sell.



06-01-2020, 08:10 AM
I would like to sell both of the servos and the auto-trim module. The A/P controller has an issue, which is why I am replacing the entire system. They no longer support the GXpilot system. I already had a GMC307 Garmin control head, so all I needed was the two Garmin servos to convert to all Garmin system. I removed the entire system yesterday and have the servos available today. Give me a call if you need them. 314 six-O-five 7744.